Opportunistic XOR-Coding Content Propagation in VANET

Abstract

Abstract-The main difference between typical wireless networks and Vehicular Ad-hoc Networks is mostly about the way traffic is propagated in these types of networks. Unlike conventional wireless networks in VANET connections are established quick and short. Because of these two factors connections in VANET are not as reliable and robust as typical wireless networks. Hence Due to these limitations in VANET and also in order to achieve higher throughput, we are aimed at investigating the adoption of network coding with the existing data propagation and routing methods in Vehicular networks. In order to address the disadvantages, we present an approach called Opportunistic Network Coding-aware Data Dissemination in Wireless Networks (NCODWN). This approach is an enhanced version of COAR. We have managed to improve network throughput and decrease end-to-end delay of the network by implementing a more efficient and reliable mechanism. The simulation results indicate that our approach outperforms COAR in terms of end-to-end delay, percentage of encoded packets, packet delivery and network throughput.Index Terms-Data propagation, network coding, vehicular ad hoc network, wireless. I. INTRODUCTIONThe emergence of wireless networks has made a crucial impact on network communications. Over the last four decades of research were conducted on the different aspects of communication between mobile networks and especially vehicular networks. One of the most important challenges in VANET is considerable rates of packet loss and insufficient throughput. Network coding (NC) [1] was introduced with the main aim of increasing the network throughput. Fig. 1 represents basic concepts of NC. In a wider overview due to nature of wireless networks, they suffer from low throughput and do not scale well in heavy implementations [2] which this problem is inherited by VANET. A. Network Coding and Routing ProtocolsIn order to utilize NC in wireless network in a practical way, one of the most well-known applications is in routing protocols. In other words, NC is applied in routing In order to create a coding-aware routing scheme. Existing NC-aware routing mechanisms in VANET evaluate links only based on possibility and impossibility of coding in nodes.Being aware of Applicable NC scenarios and opportunistic coding among different flows at certain amount of time provides the opportunity to improve the throughput of networks. Thus in order to Improve performance of existing Manuscript received January 9, 2013; revised March 27, 2014 network coding is applied. B. Opportunistic RoutingIn fact opportunistic routing is considerably different from normal routing mechanisms. In conventional routing approaches, the next hop is fixed and is responsible for sending data flows and therefore this kind of routing is not suitable for networks like VANET that their topology is dynamically changing and consequently packet drop probability is high. In contrast in opportunistic routing instead of selection of a fixed next hop, under certain circumstances a se...